Mustafa Abdul-Jalil (center l.) head of the opposition's interim governing council based in Benghazi, hugs U.N. envoy Abdelilah Al-Khatib, as Al-Khatib leaves after attending a joint press conference in Benghazi, Libya on April 1.

Tripoli, Libya — Col. Muammar Qaddafi has gained the upper hand on the Libyan battlefield, even as British and other Western officials maintain that his regime is "crumbling" from the inside.

Benefiting from a change in tactics, Colonel Qaddafi's forces have made significant gains against rebels with more nimble units that are harder for Western allies to target by air. Rebels, now lacking the curtain of airstrikes that paved their rapid westward advance last weekend, appear to be relinquishing their determination to battle Qaddafi's forces all the way to Tripoli.

An opposition leader said today that rebel forces would agree to a cease-fire if the Libyan leader pulled his loyalists out of cities and allowed peaceful protests.

The condition for the cease-fire is “that the Qaddafi brigades and forces withdraw from inside and outside Libyan cities to give freedom to the Libyan people to choose and the world will see that they will choose freedom,” said Mustafa Abdul-Jalil, head of the opposition’s Benghazi-based interim governing council.

Despite the apparent offer, the rebel aim remained toppling Qaddafi, to “liberate and have sovereignty over all of Libya with its capital in Tripoli,” said Mr. Abdul-Jalil, according to the Associated Press.

Qaddafi family envoy meets with British officials

In Britain, the defection of one of Qaddafi's closest confidantes this week and a trusted Qaddafi envoy for confidential talks in London have shifted focus from the war front to the level of support the Libyan leader still commands from his inner circle.

Mohammed Ismail, a senior aide to Qaddafi’s son Saif al-Islam, has held secret talks with British official in recent days – with speculation about negotiating a safe exit.

The report, which first appeared in the Guardian newspaper late Thursday, came as one of Qaddafi’s most senior confidantes of 30 years – former intelligence chief and foreign minister Moussa Koussa – defected late Wednesday, with more lined up to follow.

The British Foreign Office said it would not “provide a running commentary” on its contacts with senior Libyans, though a western diplomatic source told the Guardian: “There has been increasing evidence recently that the sons want a way out.”

Though subsequent reports cast doubt on Mr. Ismail's visit, saying it was personal and not mandated by Qaddafi, news of the meeting – together with Mr. Koussa's defection – have given weight to comments by Western officials that Qaddafi’s regime is fraying at the seams.

“The message that was delivered to [Ismail] is that Qaddafi has to go, and that there will be accountability for crimes committed in the international criminal court,” the Guardian quoted the Foreign Office as saying.

The US, France, and other allied nations have also stated clearly their desire for Qaddafi to go – even though regime change is not part of the mandate of the March 18 United Nations Security Council resolution, which calls for “all necessary means” to protect civilians.

Along the front lines, reports emerged of rebel forces attempting to mobilize anew against loyalist units, which have shifted tactics to minimize damage from coalition airstrikes. In many cases, loyalist forces have swapped their heavy armor – which is easily targetable by allied aircraft – for open-backed battlewagons and other vehicles that resemble those used by the rebels.

That change has complicated allied strikes in recent days, according to US Navy Chief of Operations Adm. Gary Roughead, who told Monitor editors in Boston on Thursday that Qaddafi’s forces had broken into smaller and more nimble units that are not easily distinguishable from the rebels.

“The coordination that is required for attacking, particularly small [loyalist] units, is not there simply because of the nature of the presence – or lack thereof – that’s on the ground,” said Admiral Roughead.

It was not clear how the presence of small teams of CIA operatives, now reported to be active in rebel-controlled territory in eastern Libya to help with targeting and identifying rebel needs, might begin to address that problem.

Rebels move heavy weapons, trained officers to front

Friday morning there were signs that the rebels – who in four days have been pushed back some 150 miles along the contested Mediterranean coastal road – were reassessing their military effort and moving more weapons toward the oil town of Brega.

Reuters quoted rebels in Ajdabiyah saying that only heavy weaponry was being allowed at the front, and that more trained officers would be using it. That decision comes after days in which television footage has showed panicked mass retreats, and exposed the rebels as disorganized, poorly equipped, and prone to fear.

“Only those who have large weapons are being allowed through. Civilians without weapons are prohibited,” volunteer rebel fighter Ahmed Zaitoun told Reuters.

“Today we have officers coming with us. Before we went alone,” Mr. Zaitoun told the news agency. He pointed to man stopped at the checkpoint: “He is a young boy and he doesn’t have a gun. What will he do up there?”